presencesensing

Presencesensing refers to techniques used to determine whether a person or living being is present in a space. It is used to trigger actions, collect occupancy data, or support analytics in buildings and facilities. Unlike simple motion detection, presencesensing aims to establish ongoing presence or absence over time to inform systems such as lighting, HVAC, security, and energy management.

Common technologies include passive infrared sensors, microwave or radar-based sensing, ultrasonic transducers, and camera-based computer vision. Wireless signals such as Bluetooth, Wi-Fi, and Zigbee can also indicate device presence or proximity. In many implementations, multiple sensors are combined to improve reliability, while privacy-preserving approaches focus on non-identifying measurements and on-device processing.

Applications span smart buildings, where occupancy-based control reduces energy use; security systems that detect intruders; healthcare settings that monitor patient presence; and retail analytics that track customer presence patterns. In consumer electronics, presencesensing informs smart home assistants and context-aware devices.

Challenges include privacy concerns, sensor latency and accuracy, calibration requirements, and environmental factors such as furniture rearrangements, temperature, and multi-occupant dynamics. Effective presencesensing often relies on data minimization, edge processing, anonymization, and transparent user controls to balance utility with privacy.

See also: occupancy sensing, building automation, smart home technology.